Not receiving emails from a certain domain.

[hcasaol]

We are not able to receive emails coming from a certain domain. Sometimes messages do come through, but If they do, the messages are a few days late. We are able to send to them or anywhere else just fine. I've tested from multiple external email accounts, and we receive all of my test messages instantly. I've tried Telnet and everything works fine.

Another weird thing is this company uses messagelabs to filter all incoming and outgoing messages. I've dealt directly with messagelabs about this problem. Messagelabs can send test emails to us just fine just fine, but we still can't get emails if they are sent from the other domain, through messagelabs.

Has anyone else had similar problems? I want to figure out if it is us or them.

 

[MoobyCow]

I've been on the other end. I was unable to send email reliably to just one domain.

There are several threads on this issues scattered about. The short version is that it's not uncommon to have problems sending to just one (or a few) domains. It could be because of any one of a number of different reasons.

Here are some threads on the issue:

This thread wanders a bit, but has a number of posts on the issue.

http://www.tek-tips.com/viewthread.cfm?qid=988023

This is the one that solved my problem, which had to do with setting Exchange to say HELO instead of EHLO.

http://forums.msexchange.org/ultimatebb.cgi?ubb=get_topic;f=18;t=000384;p=

 

[PuzzledUNIX]

Check AD-connectors as well.

Regards,